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Recent Results of the Auger Engineering Radio Array (AERA)
Marko Zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Ewa M. Holt, 2017, objavljeni znanstveni prispevek na konferenci

Najdeno v: ključnih besedah
Povzetek najdenega: ...Engineering Radio Array (AERA), Pierre Auger Observatory, extensive air showers...
Ključne besede: Auger Engineering Radio Array (AERA), Pierre Auger Observatory, extensive air showers
Objavljeno: 16.02.2018; Ogledov: 1731; Prenosov: 101
.pdf Polno besedilo (636,40 KB)

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Mass composition of ultra-high energy cosmic rays at the Pierre Auger Observatory
Gašper Kukec Mezek, 2019, doktorska disertacija

Opis: Cosmic rays with energies above 10^18 eV, usually referred to as ultra-high energy cosmic rays (UHECR), have been a mystery from the moment they have been discovered. Although we have now more information on their extragalactic origin, their direct sources still remain hidden due to deviations caused by galactic magnetic fields. Another mystery, apart from their production sites, is their nature. Their mass composition, still uncertain at these energies, would give us a better understanding on their production, acceleration, propagation and capacity to produce extensive air showers in the Earth's atmosphere. Mass composition studies of UHECR try to determine their nature from the difference in development of their extensive air showers. In this work, observational parameters from the hybrid detection system of the Pierre Auger Observatory are used in a multivariate analysis to obtain the mass composition of UHECR. The multivariate analysis (MVA) approach combines a number of mass composition sensitive variables and tries to improve the separation between different UHECR particle masses. Simulated distributions of different primary particles are fitted to measured observable distributions in order to determine individual elemental fractions of the composition. When including observables from the surface detector, we find a discrepancy in the estimated mass composition between a mixed simulation sample and the Pierre Auger data. Our analysis results from the Pierre Auger data are to a great degree independent on hadronic interaction models. Although they differ at higher primary masses, the different models are more consistent, when combining fractions of oxygen and iron. Compared to previously published results, the systematic uncertainty from hadronic interaction models is roughly four times smaller. Our analysis reports a predominantly heavy composition of UHECR, with more than a 50% fraction of oxygen and iron at low energies. The composition is then becoming heavier with increasing energy, with a fraction of oxygen and iron above 80% at the highest energies.
Najdeno v: ključnih besedah
Povzetek najdenega: ...production, acceleration, propagation and capacity to produce extensive air showers in the Earth's atmosphere. Mass...
Ključne besede: astroparticle physics, ultra-high energy cosmic rays, extensive air showers, mass composition, Pierre Auger Observatory, machine learning, multivariate analysis
Objavljeno: 03.04.2019; Ogledov: 2108; Prenosov: 113
.pdf Polno besedilo (17,53 MB)

26.
Mass composition of cosmic rays with energies from 10^17.2 eV to 10^20 eV using surface and fluorescence detectors of the Pierre Auger Observatory
Gašper Kukec Mezek, 2018, objavljeni znanstveni prispevek na konferenci

Opis: Ultra-high-energy cosmic rays (UHECRs) are highly energetic particles with EeV energies, exceeding the capabilities of man-made colliders. They hold information on extreme astrophysical processes that create them and the medium they traverse on their way towards Earth. However, their mass composition at such energies is still unclear, because data interpretation depends on our choice of high energy hadronic interaction models. With its hybrid detection method, the Pierre Auger Observatory has the possibility to detect extensive air showers with an array of surface water-Cherenkov stations (SD) and fluorescence telescopes (FD). We present recent mass composition results from the Pierre Auger Collaboration using observational parameters from SD and FD measurements. Using the full dataset of the Pierre Auger Observatory, implications on composition can be made for energies above 10^17.2 eV.
Najdeno v: ključnih besedah
Povzetek najdenega: ...Auger Observatory has the possibility to detect extensive air showers with an array of surface...
Ključne besede: astroparticle physics, ultra-high energy cosmic rays, extensive air showers, mass composition, Pierre Auger Observatory, fluorescence telescopes, water-Cherenkov stations
Objavljeno: 24.05.2019; Ogledov: 1545; Prenosov: 65
.pdf Polno besedilo (573,00 KB)

27.
Constraints on the diffuse photon flux with energies above 10^18 eV using the surface detector of the Telescope Array experiment
J. P. Lundquist, R.U. Abbasi, 2018, izvirni znanstveni članek

Opis: We present the results of the search for ultra-high-energy photons with nine years of data from the Telescope Array surface detector. A multivariate classifier is built upon 16 reconstructed parameters of the extensive air shower. These parameters are related to the curvature and the width of the shower front, the steepness of the lateral distribution function, and the timing parameters of the waveforms sensitive to the shower muon content. A total number of two photon candidates found in the search is fully compatible with the expected background. The 95% CL limits on the diffuse flux of the photons with energies greater than 10^18.0, 10^18.5, 10^19.0, 10^19.5 and 10^20.0 eV are set at the level of 0.067, 0.012, 0.0036, 0.0013, correspondingly.
Najdeno v: ključnih besedah
Povzetek najdenega: ...built upon 16 reconstructed parameters of the extensive air shower. These parameters are related to...
Ključne besede: Ultra-high-energy photons, Telescope array experiment, Extensive air showers
Objavljeno: 30.04.2020; Ogledov: 1048; Prenosov: 0
.pdf Polno besedilo (1,33 MB)

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New air fluorescence detectors employed in the Telescope Array experiment
J. P. Lundquist, H. Tokuno, 2012, izvirni znanstveni članek

Opis: Since 2007, the Telescope Array (TA) experiment, based in Utah, USA, has been observing ultra high energy cosmic rays to understand their origins. The experiment includes a surface detector (SD) array and three fluorescence detector (FD) stations. The FD stations, installed surrounding the SD array, measure the air fluorescence light emitted from extensive air showers (EASs) for precise determination of their energies and species. The detectors employed at one of the three FD stations were relocated from the High Resolution Fly's Eye (HiRes) experiment. At the other two stations, newly designed detectors were constructed for the TA experiment. An FD consists of a primary mirror and a camera equipped with photomultiplier tube pixels. To obtain the EAS parameters with high accuracy, understanding the FD optical characteristics is important. In this paper, we report the characteristics and installation of the new FDs and the performances of the FD components. The results of the monitored mirror reflectance during the observation time are also described in this report.
Najdeno v: ključnih besedah
Povzetek najdenega: ...measure the air fluorescence light emitted from extensive air showers (EASs) for precise determination of...
Ključne besede: Ultra high energy cosmic rays, Extensive air showers, Air fluorescence light detectors
Objavljeno: 19.05.2020; Ogledov: 871; Prenosov: 0
.pdf Polno besedilo (1,44 MB)

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Highlights from the Pierre Auger Observatory
Lukas Zehrer, Marko Zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Marta Trini, Samo Stanič, Gašper Kukec Mezek, Andrej Filipčič, Antonella Castellina, 2019, objavljeni znanstveni prispevek na konferenci

Najdeno v: ključnih besedah
Povzetek najdenega: ...ultra-high energy cosmic rays, extensive air showers, Pierre Auger Observatory...
Ključne besede: ultra-high energy cosmic rays, extensive air showers, Pierre Auger Observatory
Objavljeno: 16.06.2020; Ogledov: 913; Prenosov: 36
.pdf Polno besedilo (4,92 MB)

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Air-Shower Reconstruction at the Pierre Auger Observatory based on Deep Learning
Lukas Zehrer, Marko Zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Marta Trini, Samo Stanič, Gašper Kukec Mezek, Andrej Filipčič, Jonas Glombitza, 2019, objavljeni znanstveni prispevek na konferenci

Najdeno v: ključnih besedah
Povzetek najdenega: ...Pierre Auger Observatory, extensive air showers, event reconstruction, deep learning...
Ključne besede: Pierre Auger Observatory, extensive air showers, event reconstruction, deep learning
Objavljeno: 16.06.2020; Ogledov: 903; Prenosov: 34
.pdf Polno besedilo (1,16 MB)

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